A Life Cycle and Cost Analysis of Preemptive Mitigation, Site Characterization, and Vapor Source Reduction Strategies at Industrial VI Sites with Multiple Buildings

March 23, 2015 – USEPA Vapor Intrusion WorkshopAEHS 25th Conference on Soil, Water, Energy, and Air, San Diego, CA

Loren Lund, Christopher Lutes, and John Lowe – CH2M HILL

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Objective and Method

Objective: Determine if preemptive mitigation is most effective strategy at industrial sites with multiple buildings

Method: Quantitative Decision Analysis– Define alternatives

1. Preemptively mitigate all buildings

2. Characterize all and mitigate a few

3. Characterize, mitigate a few, and remediate source– Define criteria for making decision

– Experts objectively score how well alternatives achieve criteria– Stakeholders subjectively weight importance of criteria– Scores and weights combined for overall values for each alternative– Overall values compared with life cycle costs

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Results and Conclusions

Investigate all, mitigate VI andreduce VOC source at a fewbuildings was optimal strategyconsidering value/cost

Preemptive mitigation withlimited site characterizationmay not be optimal strategyat sites with multiple buildings

Method allows considerationof multiple decision criteria

Stakeholder subjective weights depend on their preferences It is important to consider applicable scenarios, suitability, and

sustainability prior to preemptively mitigating

$0 $5 $10 $15 $20 $25 $300

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Valu

e Sc

ore

Investigate/ Mitigate/ LTM

Preemptively Mitigate

Investigate/ Mitigate/ SVE/LTM

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